A total of 4 NIH investigators that constitute the major users and 2 other federally-funded investigators that represent minor users request funds to support purchase of a MALDI mass spectrometer with MS/MS capabilities and associated sample separations and sample preparation equipment. This instrument will be placed in the growing WSU Mass Spectrometry and Proteomics Core Facility and will more efficiently handle the large number of samples that are currently dependent on a 10 year old ABI Voyager MALDI-TOF that is becoming difficult to maintain due to availability of parts. In addition, this instrument will enable new capabilities for MS/MS analysis of MALDI-generated ions that is currently not possible at WSU. The requested instrument will dramatically expand the Core Lab abilities to provide peptide mass fingerprint and MS/MS-based protein identification information that is critical to many NIH-funded projects on the WSU campus and on the nearby University of Idaho campus. Specific NIH-funded projects outlined in this proposal that will constitute major users of the technology include, proteomics experiments to identify secreted proteins that mediate cell-cell interactions involved in testis development and primordial follicle development (Co-Pi Skinner), phosphoproteome profiling to study the regulation of retinoic acid receptor effects on testis development (Co-Pi Kim), protein-interaction studies to investigate molecular components of cellular motility (Co-Pi Cole) and proteomics investigations of immunoresponse relevant to Anaplasma maginalis (Co-Pi Brown). Large-scale proteomics research is becoming increasingly critical in these projects and in many others and the requested instrumentation enables the WSU Core Lab to support this research. [unreadable] [unreadable]